How to implement an average filter ? (solved)

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#How to implement an average filter ? (solved)

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kaxori 06/26/2023 05:54 PM

Today I wanted to implement a ripple filter for the noisy ESP32 ADC data. Searched through example sources and libs, but with used keywords I was not successful.
Then i tried to implement a filter, building average of n recent values stored in a list. But got compiler errors after removing oldest/first list element (values = values[1...].
Not only the language detailed, also the concepts are hard to find.

Which resources do you recommend to learn to solve such simple problems ?

theHuanter 06/26/2023 06:13 PM

I recently made a little package for a ringbuffer which has the function to average its values

theHuanter 06/26/2023 06:13 PM

https://github.com/Informaticore/toit-ringbuffer

GitHub - Informaticore/toit-ringbuffer: A RingBuffer implementation...

A RingBuffer implementation as a data structure that stores a fixed number of elements and overwrites the oldest elements once the maximum size is reached. - GitHub - Informaticore/toit-ringbuffer:...

floitsch 06/26/2023 06:20 PM

I think the average in your code is correct.

floitsch 06/26/2023 06:20 PM

Just be careful that the way you use reduce requires at least two elements.

floitsch 06/26/2023 06:21 PM

If you use --initial=0 (or a different value, depending on the context), then you can also call reduce with just one function.

floitsch 06/26/2023 06:22 PM

nit: generally, we don't add a space after the reduce. So it should be reduce: | a b | ....

floitsch 06/26/2023 06:23 PM

aah. I can see you are actually using your own reduce, not the one from List.

floitsch 06/26/2023 06:24 PM

And I'm now realizing I didn't actually answer to the original question...

theHuanter 06/26/2023 06:24 PM

but feel free to open an issue or something so the input does not get lost

theHuanter

but feel free to open an issue or something so the input does not get lost

floitsch 06/26/2023 06:28 PM

Not sure it's worth filing an issue.
I would:
- remove the spaces (after reduce).
- hide reduce or make it more intuitive. Currently it runs from 0 to count. I would have expected it to run from oldest to newest.

OPkaxori

Today I wanted to implement a ripple filter for the noisy ESP32 ADC data. Searched through example sources and libs, but with used keywords I was not successful. Then i tried to i...

floitsch 06/26/2023 06:30 PM

Note that the Adc.get function already runs 64 samples and averages them.
You can change that by passing in --samples=1 (for example).

floitsch

Note that the Adc.get function already runs 64 samples and averages them. You can change that by passing in --samples=1 (for example).

kaxori 06/26/2023 06:40 PM

Magical: on page https://libs.toit.io/gpio/adc/class-Adc, where can i find such conceptual infos?

floitsch 06/26/2023 06:40 PM

have a look here: https://docs.google.com/document/d/1K-TYea7jbYfj2ecMUmr0T0zd4JDpk5lo0mJNOLPUrhc/edit?pli=1

MakePython ESP32 Dev Kit

Get Started with Toit This document provides simple instructions on how to get started with Toit. It is loosely inspired by Makerfab's MicroPython course and uses the same hardware. In Europe the kits are available here: https://hitechchain.se/en/makerfabs/29-iot/makepython-esp32-dev-kit If you ...